This invention relates to a recording medium in which a chemically modified proteinaceous compound containing therein no intermolecular cross-linking bond is used as a recording component.
With regard to light-sensitive media using a protein and its derivatives, J. Kosar, Light-Sensitive Systems, page 62, John Wiley & Sons, Inc. (1965) describes that albumin is made insoluble on application of ultraviolet rays in the presence of dichromates and this phenomenon can be utilized in an egg white photographic printing plate, and Journal of Applied Polymer Science, 7, page 273 (1963) describes that a mixed system of 3-azidophthalated gelatin and a naphthothiazoline based sensitizer is made insoluble on irradiation with light.
Furthermore, with regard to recording media using thermally coagulatable proteinaceous compounds in which a recording layer is selectively changed by application of a heat pattern to form a latent image, and unchanged areas of the recording layer are then removed to form a recording image, U.S. Pat. No. 4,115,613 (corresponding to British Pat. No. 1,572,073) and Japanese Patent Application (OPI) No. 15817/80 (the term "OPI" as used herein refers to a "published unexamined Japanese patent application") disclose a heat-sensitive recording layer containing therein a high molecular weight proteinaceous compound.
Recording using these recording media is performed by irradiation with xenon flash light, laser light, and so on. If the recording could be performed by irradiation with low energy light, it would be possible to use a light source which is of low output, inexpensive, and has a long service life. This could lead to miniaturization and cost reduction of the light source apparatus. It has therefore been desired to develop a recording medium which is capable of providing a sharp and stable recording image by irradiation with low energy light.